Material:Quality material,Durable to UseLightweight, Long Lasting.Suitable for most hard drive installations.Note: Applicable to the chassis of most slide rail hard drives, But it is not guaranteed to be suitable for your chassis.Because of the installation of the chassis, there is no uniform standard, the store can not access these hardware, can not provide advice Type: Hard Drive RailsModel number: for 3.5 to 5.25 Hard Drive HDD Tray Caddy cage rackcolour:BlackMaterial:plasticsize:13.5 x 1.5 x 0.5cmPackage Contents:10 Pairs x Hard Drive Rails Only the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.